An air conditioner is a home appliance that cools or/and heats a room by heat-exchange of refrigerant that flows in various components constituting a heat-exchange cycle, and indoor air and outdoor air. A separate type air conditioner among the air conditioners is constituted by an indoor unit and an outdoor unit. In addition, a compressor constituting the heat-exchange cycle is installed in the outdoor unit. The compressor serves to compress refrigerant that circulates throughout the heat-exchange cycle.
Vibration and noise are generated by rotation of a motor, and the like while the compressor compresses the refrigerant. In the related art, a member for sound absorption or sound insulation is used in order to prevent noise generated while the compressor operates from being generated. For example, a member molded as a fiber material serving to perform a sound absorption function or/and a rubber material serving to perform a sound insulation function is installed to surround the compressor to thereby absorb noise generated while the compressor operates or prevent noise from being leaked to the outside.
Meanwhile, the member for sound absorption or/and sound insulation in the related art substantially has sound absorption or/and sound insulation characteristics to a frequency band over approximately 1000 Hz. However, the compressor has relatively large noise in a frequency band of 1000 Hz or less when the compressor operates. Accordingly, in the related art, efficient sound absorption or/and sound insulation cannot be substantially achieved with respect to noise in a predetermined frequency band generated from the compressor.